Bowling-pin construction



L arch 12; 1929. R. s. BLAIR lfl i q aowuue PIN cous'rnucupu,

Filed April 26. 1923 M INVENTOR Patented Mar. 12, 1929. FUNlTED STATES I 1,705,280 Parser ori ice; 9

ROBERT S. BLAIR, OF STAMFORD, CONNECTICUT.

- BOWLING-P11! CONSTRUCTION.

, Application filed April 26,

by such articles may be manufactured conveniently and at low cost. Otherobjects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, arrangements of parts and in the sev oral steps and relation and order of each of the same to one or more of the others, all as will be illustratively described herein, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which is shown one of the various possible embodiments of the mechanical features of this invention,

Figure 1 is a side elevation of a bowling pin the lower portion being cut away;

Figure 2 is a bottom view of the bowling pin at one stage of the process of manufacture;

Figure 3 is a diagramniiatic view insection representing another step of the process; and Figured shows the bowling pin in a still further step of manufacture.

Referring now to the drawing in detail, there is shown a bowling pin having a main body portion 1.0 formed preferably of wood and shaped to the desired contour of such devices in the usual manner, as by turning down the wood in a suitable lathe. It may be here noted that bowling pins in order to obtain the qualities most desired are generally made of a tough, resilient wood. In forming the pins they are carefully balanced and proportioned so that the center of gravity may fall at substantially the de sired point and in orderthat they maystand in an upright position with. substantially the desired degree of stability. In order-that the pins may retain their ability to thus stand erect and with the desiredstability it is required that their bases be carefully lev-' eled' and thereafter be maintained in such condition. The wooden pins are subjected to.

1923. Serial No. esecsif i extremely rough usage and without'added protection their bases soon become dented and marred'to such an extent that the pins are no longer capable of standing with the stability that was originally intendech The provision of means for overcoming such difficulties without disturbing the balance and general substantial homogeneityof the bowling pins is an aim'of this invention.

In Fig. 2 there is shown a bottom View of the wooden pin 10 and formed therein, as by turning, is an annular groove 11 preferably dove-tailed shapein cross section, as is seen more clearly in Fig. 3. Upon the'groove 11 having thus been formed, the pin is inverted and a mold 12 is clamped about. the lower portion thereof.

or protective material which upon hardening within the mold forms a surfacing or cap 14, as shown in Figs. 1 and l, interlocked with the annular recess 13. The material 14: is preferably a metal alloy having a low melting point and a specific gravity as near as practicable to thatof the wood ofthe pin 10,

for example, an alloy of lead, 10; tin, 24;

and bismuth, 66. The. temperature of the molten alloy is not high enough to cause the wood to char and, being of substantially low specific gravity, doesnot materially detract from the general homogeneity of thepin. In fact, the wood may be hollowed outas indicated at l0, if desired, to con'ipensate for the excess weight of the metal.

As is Well known, with alloys of the above nature, they are not only fusible at 'a low temperature. but, on, solidifying, tend to expandinstead of to contract, as do most metals and alloys, This expansion increases the tightness .of the joints and the security of attachment of the parts.

The inner wall 12 of the mold. 12 is preferably convex so that the cap or covering 14 is formed with a central depression 14 sur rounded by an annular level sorta-cele As is clearly shown in the drawings, a plug is fitted in the lower-end of the cavity 10 in order to prevent the entry thereinto of the molten. alloy and thus allow the cavity to.

compensate for the weight of theinetalas above set forth. In order to true or level the bottom surface or base of the pin and thus insure its standing in the desired erect position, the pin is preferably suspended by Into the mold 12' through a suitable gate 18 therein is poured 111 amolten condit on a suitable reinforcing a spring 15 and a planehorizontalgheated surface 16 is brought into contact with the surface 14". In this manner the alloy surface 14;" is fused slightly and the pin being suspended through its vertical center-line, and the surface 16 being horizontal, the base surface of the pin will be molded so that it conforms to a plane substantially at right angles to its line of suspension. Thus the pinis provided with a base upon Which it will stand in a true'erect position. The relatively hard and strong alloy will not easily become dented and marred but will retain its original conformation for a long period of time under the most severe use. The surfacing furthn serves to reinforce thewooden portion of the pin against splitting.

From the above it will be seen that there are herein provided a device and art of making the same which embody the features of this invention and attain the objects thereof.

As many possible embodiments may be made of the mechanical features of the above invention andas the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpretedas illustrative and not in a' limiting sense.

' I claim as my invention:

1. The here-in described art which consists in casting on the base of a bowling pin a protective material into interlocking relation therewith, said material consisting-of a readily fusible alloy tending to expand on solidification. r

2. The herein described art which consists in forming an annular recess in the lower portion of a bowling pin, pouring thereinto a molten material in an amount to fill said re 23. The herein described art which consists in forming a recess in the base of a bowling pin, fitting a mold againstthe lower portion of said bowling pin the inner Walls thereof being spaced from said base, pouring a molten material into said mold and said recess through the Wall of said mold and toward the pin, and permitting said material to harden therein forming a covering for said base interlocked with said recess.

l. The herein described art which consists in surfacing the base of a bowling pin with a metal alloy of low melting point, suspending said bowling pin in anupright position, and applyin a heated surface to said surfacing to level the same.

5. The herein described art which consists in suspending a bowling pin and applying means to the base thereof to level the same.

6. The herein described art which consists in forming a recess in the bottom of a bowling pin and forming on the hotom of said pin enteriorto said recess a metallic protective" member leaving said recess free from metal whereby the effectof the metal upon the center of gravity of the pin may be neutralized by the effect thereon of said recess.

7 The herein described art which consists in forming a recess in the bottom of a pin, forming a second recess in the bottom of the pin, and casting a metallic protective member into said second recess, leaving said; first recess unfilled.

8. The herein described art which consists in forming an annular recess in the lower portion of a'bowling pin with undercut walls,

v and casting into said recess molten metallic material and allowing said niater'al to harden therein to form a reinforcement for the pin. r

9. The herein described artwhich consists in forming a recess in the base of a bowling pin, mounting a mold upon the base of the pin, the central portion of the inner wall of which is nearer the pin than the outer portions, and casting a metallic reinforcement in said mold into interlocking relation with said recess.

In testimony whereof, I have signed my name 'to this specification this 20th day of April, 1923." r

ROBERT S. BLAIR. 

